Improvement in piano-fortes



2 Shees--Sheet 2.

C. F. Ti STElNWAY. improvement in Piano-ortes. N0. @Q7/,383, j'z/:Patented May 28,18'72.

UNITED STATES PATENT GEEIGE.

C. F. THEODOR STEINVAY, OF NEW YORK, N. Y., ASSIGNOR .IO HIMSELF, ALBERTSTEINWAY, AND WILLIAM STEINWAY.

IMPROVEMENT IN PIANO-FORTES.

Specification forming part of Letters Patent No. 127,383, dated May 28,1872.

To all whom it may concern:

Beit known that I, G. F. TnEonoR STEIN- WAY, of the city, county, andState of New York, have invented a new and useful Improvement inPiano-Fortes; and I do hereby declare the following to be a full, clear,and exact description thereof, which will enable those skilled in theart to make and use the same, reference being had to the accompanyingdrawing forming part of this specication, in which drawing- Figure lrepresents a plan or top view of a grand piano-forte constructedaccording to my invention. Fig. 2 is au inverted plan of the same, thebottom of the case having been removed. Fig. 3 is a transverse sectionof one of the wedge-braces of my metal frame in the plane x m, Fig. 2.Fig. 4 is a sectional end view of my metal frame and the partssupporting the same. Fig. 5 is an inverted plan of the metal fra-medetached. Fig. 6 is a plan of the bottom of my case detached. Fig. 7 isa longitudinal section of the same in the plane y y, Fig. l. Fig. 8 is asection of the sounding-board in the plane a" x', Fig. 1, showing theconstruction of my sounding-board bridge. Fig. 9 is a transverse sectionof the same in the plane y yf, Fig. S.

Similar letters indicate corresponding parts.

This invention relates to a piano-forte the metal frame of which isarched at its ends and provided with a flange, which serves to fastenthe same down to the wooden frame.

On the under surface of this iiange are formed projections, which reston dowels secured in the frame supporting the soundingboard, andextending above the surface of said sounding-board, so as to leave thesounding-board free to vibrate Without coming in contact with the metal,while, at the same time, the metal frame is rmly supported.

From the inner surface of the wrest-plank part of my metal frame projectone or more brackets, each forming the bearings for a metal wedge whichbears against wooden braces bearing against the outer rim of the woodenframe supporting the sounding-board, whereby the metal frame isstrengthened against the tension of the strings. The metal frame on itsupper surface is provided with lugs for the reception of a metalwedge-bar, which extends obliquely over the treble-strin gs and assistsin strengthening the frame against the tension of the strings.

The bed-plate or bottom of my wooden case is formed of two thicknessesof wood, the lower layers of which extend, in a longitudinal direction,from one end of the bed-plate to the other, while the lower Atransverselayers are secured between them, the upper transverse layers extendingacross the lower longitudinal layers in such a manner as to produce abedplate very light, and yet of great strength, and capable of resistingthe pull of the strings.

In the drawing, the letter A designates the wooden case of a grandpiano-forte constructed in the usual manner, and supported by legs B.The bottom or bed-plate C of this case is shown in Figs. G and 7. It isconstructed of two layers of wood, which are fastened to each other inthe following manner: The lower layer consists of two strips, a al,which extend throughout the entire length of the bottom on its sides,and the ends of which are connected by the lower cross-strips fastenedbetween them, and by the upper transverse end strips b b1, which extendacross them, as

shown in Fig. 6. In addition to the upper transverse end strips b b1 asecondary transverse strip, c, is fastened on the lower longitudinalstrips a a1,- but this secondary trans` verse strip abuts on one endagainst a longitudinal strip, d', which rests upon the lowerlongitudinal strip a1. Between the upper transverse strips b c and o b1are inserted longitudinal side strips c e e e, and, in addition tothese, I connect the transverse strips b c by intermediate longitudinalstrip ffj', the interstices between these last-named strips being filledout by panels g. By these means a bottom is obtained which combinessuperior lightness with great power of resistance against the tension ofthe strings.

The construction of my case will be best understood by referring to Fig.2, which shows an inverted plan of the same when its bottom has beenremoved. The rim of this case is composed of rectilinear timbers h h1and a curved part, i, which latter part is, by prefer` ence, made of anumber of layers of veneers glued on each other and pressed in thedesired forms. On the rectilinear timbers h h1 of the case is securedthe wrest-plank D, and inside of this wrest-plank said timbers areconnected by a cross-bar, E, which, together with the edge of the case,forms the support for the sounding-board F. Between the crossbar E andthe rim of the case I apply three longitudinal braces, j k l, two ofwhich converge toward one point of said cross-bar, as shown in Fig. 2,while the third passes from this cross-bar to the curved portion of therim. With these longitudinal braces and the rim are combined two or morecross-braces, m m. The sounding-board F is fastened to the top edge ofthe case A, and of the cross-bar E, by means of glue or in any otherdesirable manner, and it is exposed to the action of compressing-screwso, which screw into the edge of the sounding-board, (se'e Fig. 1,) andthe heads of which bear against a metallic bridge, G, extending from thecross-bar E to one of the cross-braces m. H designates the metal frame,which is made arched or with a curved edge, p, from which projects aretainin g-iian ge, q. (See Figs. 4 and 5.) This ila-nge extends overthe curved portion of the rim of the case A, and it is provided on itsunder surface with projections o", which bear on dowelpins r rising fromthe rim of the .case A through the sounding-board, and projectingsomewhat above the surface of the same. By means of these dowel-pins themetal frame is kept out of contact with the sounding-board, leaving thesounding-board free to vibra-te without obstruction by the metal. Saiddowelpins are arranged in pairs close to the edges of the ribs t of thesounding-board, and they assist in giving strength to the connectionbetween the sounding-board and the case A.

By means of these dowel-pins the metal frame can be readily adjusted inposition, so that the same will be supported uniformly at all points,since said dowel-pins can be readily shortened and adapted to theformation ofthe dan ge q of the metal frame.

The front end of the metal frame is firmly screwed down upon theWrest-plank D, and this front end connects with the arched rear portionthereof by means of'a series of connecting-bars,o. (See Fig. 1.) Fromthe under surface of the front part of the metal frame project one ormore brackets, w, one being shown in Fig. 2; and if the metal frame isin position this bracket is opposite to the point toward which thelongitudinal wooden braces 7c l of the case A converge. By insertin g ametallic wedge, a2, between the end of the bracket fw and the cross-barE, the metal frame is materially strengthened against the tension ot'the strings. On the treble end of my metal frame are c ast two lugs, b2,for the reception of a wedge-bar, c2, which is driven in after thestrings have been adjusted, and which serves to strengthen the metalframe against the tension of the strings. It will be noticed that theobject of this treblewedge is the same as that of the treble-bardescribed in my patent No. 97,982, and forming the subject-matter of thethird clause of the claim in said patent.

By using a loose wedge-bar in place of said treble-bar, the operation ofadjusting the treblestrings on the hitch-pins is materially facilitated,sincev vthis purpose can be easily effected before the wedge isinserted.

The strings in their course from the hitchpins to the tuning-pins bearon the soundingboard bridge I, which is provided with a strip, d2, ofbrass or other metal, (see Figs. 8 and 9,) that may be secured to eitherside or to the top of the bridge, or which may be let into the bridge,as shown.

A dat strip of metal or a piece of metal wire may be used for thispurpose. By this piece of metal the quality of the bridge to transmitthe vibrations of the strings to the entire sounding-board, or to thatportion of the sounding-board supporting said bridge, is materiallyincreased, and the tone of the instrument is improved.

The strings s of my piano-forte are supported between the agraii'es f2and the tuningpins and between the bridge-pins g2, and the hitch-pins bybridges h2, which I term the nodal bridges, and which are adjusted atpoints corresponding toone of the nodes of the strings.

By embodying the above-described features in a piano-forte I am enabledto reduce the size of the instrument, while the tone reta-ins its fullstrength, or is rendered even superior .in strength and brilliancy tothat of instruments constructed according to my former patents; and,furthermore, the cost of my new instrument is materially decreased.

These improvements are designed principally for grand piano-fortes, butmost of them are applicable to upright and also square piano-fortes.

What I claim as new, and desire to secure by Letters Patent, is-

1. The bed-plate C for the case of a pianoforte, constructed oflongitudinal bottom strips a al, transverse top strips b-b1 c, andlongitudinal top strips el e c f, all combined in the manner hereinshown and described.

2. The arched edge p and flange g on the metal frame II of apiano-forte, substantially as set forth.

3. The projections 1 on the flange q of the metal frame H, substantiallyas described.

4. The supporting dowels r 1^ secured in the rim of the wooden caseA,incombination with the metal frame and sounding-board of a piano-forte,substantially as set forth.

5. The bracket w and wedge a2, in combina tion with the metal frame Hand with the converging braces k l of the wooden case A, substantiallyas described.

6. The treble-wedge c2 and lugs b2 upon and in combination with the barc and outside border of the frame H, substantially as described.

' C. F. THEODOR STEINWAY. Witnesses:

W. HAUFF, E. F. KAsTENHUnER.

